Electronic Supplementary Material (ESI) for Journal of Materials Chemistry C. This journal is © The Royal Society of Chemistry 2015

Electronic Supplementary Information (ESI)

CO catalytic oxidation on Al-doped graphene-like ZnO monolayer sheets: a first-principles study Dongwei Ma1,, Qinggao Wang1, Tingxian Li1, Zhenjie Tang1, Gui Yang1, Chaozheng He2,, and Zhansheng Lu3

1School of Physics, Anyang Normal University, Anyang 455000, 2Physics and Electronic Engineering College, Nanyang Normal University, Nanyang 473061, China 3 College of Physics and Electronic Engineering, Normal University, Xinxiang 453007, China

Corresponding author. E-mail: [email protected] (Dongwei Ma). Corresponding author. E-mail: [email protected] (Chaozheng He). (a) Ea = 0.02 eV (b) Ea = 0.02 eV (c) Ea = 0.02 eV d = 3.23 Å d = 3.08 Å d = 2.97 Å

(d) Ea = 0.03 eV (e) Ea = 0.01 eV d = 2.91 Å d = 3.22 Å Fig. S1. Several atomic configurations for the O ((a), (b), and (c)) and CO ((d) and Fig. S1 2 (e)) adsorption on the pristine g-ZnO monolayer sheet. The nearest distance between the adsorbed molecules and the sheet, and the adsorption energies are given.

2.12 Å 1.39 Å 2.13 Å 2.14 Å 1.39 Å 2.09 Å

(a) E = 0.86 eV (b) E = 1.15 eV a a

Fig. S2. Atomic configurations of two typical states for the O2 adsorption at the sites away from the doped Al atom on the Al-g-ZnO monolayer sheet. The adsorption energies are given. Fig. S2 (a) (d)

Ea = 0.13 eV Ea = 0.04 eV

(b) (e)

Ea = 0.24 eV Ea = 0.11 eV

(c) (f)

Ea = 0.15 eV Ea = 0.23 eV

Fig. S3. The atomic configurations and adsorption energies for the states of O2 dissociative adsorption on the Al-g-ZnO monolayer sheet. The O atoms from the

dissociated O2 are denoted as blue spheres. The adsorption energies were calculated with respect to the free O2 molecule and the bare Al-g-ZnO sheet.

(a) 3.22 Å 2.18 Å 1.94 Å 2.10 Å

1.60 Å 1.66 Å (b)

2.08 Å 2.03 Å 2.30 Å 2.96 Å

Fig. S4. Atomic configuration of the considered initial (left) and fully optimized (right)

states for the coadsorption of O2 and CO molecules on the Al-g-ZnO monolayer sheet.

Fig. S3

2.54 Å

1.48 eV

(a) (b)

Fig. S5. Atomic configuration of the carbonate-like MS state and the state of CO2 physisorbed on the atomic O-covered Al-g-ZnO monolayer sheet are shown in (a) and (b), respectively. The former is more stable than the latter by 1.48 eV. Fig. S4